Environment Stony corals discovered on manganese nodules for the first time
In the depths of the Pacific, a team has discovered for the first time a species of stony coral that grows on manganese nodules. These are the mineral-rich rocks that are arousing increasing interest in deep-sea mining worldwide.
25.11.2025, 05:52
SDA
"It lives directly on the nodules that are to be mined for the industry," said co-study leader Nadia Santodomingo from the Senckenberg Research Institute and Natural History Museum in Frankfurt.
The specimens of stony coral were found at a depth of over 4000 meters in the Clarion-Clipperton Zone. According to the Senckenberg Gesellschaft für Naturforschung, this area between Hawaii and Mexico is home to the world's largest deposits of manganese nodules. These extremely slow-growing, potato-sized lumps of minerals are rich in metals such as manganese, nickel and cobalt.
"Unique, ecological relationship"
Settling on the nodules "marks a unique ecological relationship that has been documented for the first time in this way for a deep-sea stony coral," the company writes.
"If these nodules are removed, we risk the extinction of an entire species that we have only just discovered," said Santodomingo. The team named the newly discovered coral species Deltocyathus zoemetallicus and described it in the "Zoological Journal of the Linnean Society".
During several expeditions on board two research vessels, the group had collected both manganese nodules and specimens of the stony coral. Corals of the genus Deltocyathus are said to occur worldwide, with the exception of the Arctic and the waters around Antarctica. However, they usually grow at much shallower depths and mostly lie freely on the sediment.
Coral grows in the dark
According to the team's description, the coral Deltocyathus zoemetallicus lives in complete darkness, without symbiotic algae and feeds on floating particles in the water. According to the researchers, some specimens come from depths where calcium carbonate is already beginning to dissolve. As the hard skeleton of the coral is also made of it, this indicates a special adaptation. According to the study, bryozoans, sponges and soft corals were previously found on the manganese nodules.
"This discovery shows how little we know about life in the deep sea," said Guadalupe Bribiesca-Contreras from the National Oceanography Center in Southampton, UK, who led the study together with Santodomingo. "It's about preserving a whole world of deep-sea life that could disappear before we even know it exists," added Santodomingo.
